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Action n° 63 du Programme 2010 au titre de l'accord cadre Agence de l'Eau ZABR

Over the past 50 years rice cultivation in Asian deltas has undergone impressive intensification. In the Chao Phraya Delta, Thailand, traditional deepwater and floating rice varieties have gradually been replaced by high-yield varieties (HYVs). However, until recently a floodplain of 300, 000 ha was still cultivated with traditional varieties. We analyze how these varieties came to be replaced by single/double cropping of HYVs and describe the new water regime that has been established, taking the Bang Kum drainage basin as an illustration. While the shift brought a welcome increase in rural incomes, we show how the change in water management has had serious negative cross-scale consequences that have not been considered. We end by discussing the government’s plan to alter the water regime in the area again, as part of its “monkey cheek” (flood retarding) policy. We show that rather than enhancing management flexibility and the floodplain’s buffering capacity, as it claims, this policy in fact undermines both.

Dans le sud de la France, les canaux d’irrigation gravitaire témoignent d’une maîtrise séculaire de l’eau par les sociétés locales. Mais aujourd’hui, le devenir de ces aménagements (appelés « béals » en Cévennes gardoises) ne va plus de soi. Leur présence dérange, s’articulant difficilement aux nouvelles injonctions de partage et de qualité pour la gestion de l’eau (lois sur l’eau 1992, 2006). Pour résoudre des situations devenues problématiques, un processus de modernisation - institutionnel et technique - des canaux a été initié par l’Administration. À partir d’un travail de terrain en Cévennes auprès des sociétés d’irrigants composant avec la modernisation de leurs béals, cet article étudie les réactions et interrogations des habitants face à une conception administrative des canaux afin d’interroger la rencontre entre des modes de relation des acteurs à l’eau., In the South of France, gravity-fed irrigation canals embody centuries-old experience in water management in response to the high variability of rainfall across space and time. But nowadays, the sustainability of these works (called "béals" in the Cévennes gardoises) is no longer given and their very existence comes in the way of the adaptation to the new regulations concerning water sharing and quality (water laws 1992, 2006). To address a situation that has become problematic, a process of modernisation (institutional and technical) of the canals has been initiated by the Administration. Based on fieldwork in the Cévennes with irrigators' associations dealing with the modernisation of their béals, the aim of this paper is to discuss the actors' relationship to water through the study of local reactions to, and questions about, an administrative conception of these works that denies the values and knowledge associated with them.

Les crises écologiques, les politiques pour les contrer, la croissance des inégalités résultant de la mondialisation et des politiques libérales ont revitalisé la notion de justice environnementale. Cette notion veut comprendre les interrelations entre les inégalités sociales et l'environnement : quel environnement, où, et pour qui ? Des chercheurs se sont emparé de ce concept d'origine nord-américaine, alors peu connu dans le champ académique français, pour jeter un regard neuf et critique sur les politiques environnementales. S'attachant à décrypter des situations d'échelle locale, régionale ou globale en observant aussi bien des espaces urbanisés du Nord que des espaces ruraux du Sud, ils examinent la mise en œuvre du développement durable, la protection contre les risques naturels, les opérations de rénovation urbaine ou d'implantation d'équipements polluants, la gestion des bassins hydrographiques, l'accès au foncier ou encore les aires protégées. Les analyses en termes de justice environnementale mettent en évidence un certain nombre de contradictions entre les dimensions sociales et environnementales des politiques menées au nom de la protection ou de l'amélioration de l'environnement et permettent d'en imaginer de plus justes.

In no other country, perhaps, is the identification between water, irrigation, and agriculture as strong as in Egypt. Several phases of agrarian and technical change throughout its long history have taken Egypt to a situation where farmers grow between one to three crops a year on 3.78 million ha after lifting water from canals and drains, and sometimes from aquifers. This chapter first reviews the extraordinary cost of maintaining the delta 'irrigation machine', the history of irrigated agriculture expansion, and the evolution of public policies. It then examines key issues and challenges, including irrigation modernization, the search for water savings, the multiple experiences with participatory management at various scales, inter-sectoral integration, the water-food-energy nexus, the recent masterplan, and finally transboundary threats.

This chapter presents an introductory description of political, technological and institutional change in the field of irrigated agriculture in the Mediterranean area. After a brief description of the main characteristics of irrigation in this world region, the chapter introduces the eight national chapters : the cases of Tunisia and Morocco in the Maghreb ; Spain, France and Italy in the European Union ; and Turkey, Israel and Egypt on the oriental shores of the Mediterranean Sea.

In a context of major changes (climate, demography, economy, etc.), the Southern Mediterranean area faces serious challenges with intrinsically low, irregular and continuously decreasing water resources. A method for translating a narrative scenario of irrigation water requirements into a quantitative scenario is presented. At first, we propose to describe the Irrigation Water Requirements (IWR) of any area by a single equation. IWR depends on climate (ET0, Rainfall), crop development estimated from remote sensing time series (crop coefficient/NDVI relationships), and four efficiencies parameters. In a second part, a reference model of the crop coefficient monthly cycle ( ) is proposed by empirically relating to rainfall and NDVI. Three variations of the model are compared in order to make a projection until 2050 based on downscaled climate change scenarios. The reliability of the model depends on the representativeness of the calibration period: It is considered to be high at the beginning of the simulation (RMSE below 0.1), but it deteriorates as the calibrating period gets shorter compared to the objective period: r2= 0.5, RMSE = [0.1-0.14], stderr = [0.02-0.03] by 2050. An alternative scenario is built upon the reference by interpreting the narrative as bending points. Finally, the examination of irrigation water demand until 2050 suggests that the difference between the two climate scenarios is very small (